The main focus of the upcoming 1.30.2 balance update has been the nerfs to Night Elf who's reigned supreme in patch 1.30. Have these nerfs overshadowed some other quite relevant changes? Let's take a look at Control Magic!
If I am being completely honest, I'm not sure I've ever seen Control Magic being used - at least I can't remember it. You might also only be vaguely familiar with this obscure upgrade to Spell Breakers, so let's have a look of what ability actually does.
Pre-buff Control Magic. Source: Liquipedia
With the upcoming balance update Control Magic will change in two ways:
One general thing that should be noted about Control Magic is, that the initial cast cost of the ability is 25 mana. So the actual cost is and will be 45/35% of enemy HP PLUS 25.
Now, the big kicker of these two changes is definitely the upgrade being available with Keep (tier 2) instead of Castle (tier 3). In the scenarios where Spell Breakers are common, you'll usually not try to get tier 3, so most of the time the ability simply wouldn't be at your disposal. It is a cheap upgrade with a quite reasonable research time, so with it being ready on tier 2, it is very convenient to get it.
With the accessibility cleared, let's take a look at how useful the ability will be. Spell Breakers start with 75/250 mana when they first pop out of the Arcane Sanctum. That isn't that magnificent, but assuming you have Archmage with Brilliance Aura, which is a quite fair assumption, and a decent amount of Spell Breakers, mana shouldn't be that big of an issue.
Another important consideration is how likely you are to face summons, and, to varying degree, you are actually quite likely to face summons in all four match-ups (Water Elementals, Treants, Spirit Wolves and Skeleton Warriors).
As seen below I've compared the mana cost of current Control Magic to the buffed Control Magic, looking at some of the more popular summoned units at full HP.
Control Magic table
I actually expect these changes to have a quite important impact. Imagine Human mirror, where it's very common to have a lot of Spell Breakers. You don't really have any occasion to ever use Spell Steal, so your Spell Breakers will certainly have plenty of mana. With the new Control Magic, full mana Spell Breakers can snatch up a newly summoned level 2 Water Elemental, or even a level 3 Water Elemental if you just damage it a little - that's HUGE!
Also against Orc players playing with Far Seer you can invalidate one of their most important spells, Feral Spirit.
What are your thoughts on the new Control Magic? Do you think it'll force players to reinvent Human mirror or do you think Control Magic will stay a rare sight in competitive play?